Answer:
1.3905 × 10^4
Step-by-step explanation:
First you should multiply all the two numbers inside the parentheses
5.7 × 105=598.5
4.6 × 106=487.6
2.9 × 105=304.5
Now add the three numbers
598.5+487.5+304.5= 1390.5
scientific notation: Put the decimal after the first digit. To find the exponent count the number of places from the decimal to the end of the number.
the answer in scientific notation: 1.3905 × 10^4